Well my light came on a while back, just happen to be raining out. I tried draing the filter, didn't work, then I put a new filter on, still didn't work. Is my sensor just bad is there someway to check it?
Heath

 

They do go bad over time, might try some electric contact cleaner and see if it will dry it up,if not then a new one is in order. Goodluck,,Rick

 

Usually it's just crud at the bottom of the filter shorting it. I just wipe it with a rag when changing filters.
Sometimes if it gets wet under the hood the connector near the bottom of the filter will short out and can take quite some time to dry out.

 

i had the same problem,and i changed the filter and the sensor which did not help.The problem with mine was the connector plug getting wet everytime it rained or sometimes even puddles or washing. I took the connector apart, cleaned the contacts with contact cleaner and applied lots of dielectric grease to both sides and havent had a problem since. Good luck!